07 Nov 2017 / Leonardo Barichello

If you are starting a more "professional" academic journey, as a master or PhD student, I strongly recommend that you use a reference manager to help you organize and keep track of the things you read.

The two main roles of a reference manager are: a) help you organize papers and books you read and b) facilitate citation and referencing when producing your own text. The most common options I know are EndNote, Mendeley and Zotero. The first is paid and proprietary. The second is free (of charge) but not open source (although very friendly with users). The latter is free (of charge) and open source, so it is my choice!

zotero's logo

Below, I will present basic steps to set up Zotero, recommend some good practices, offer some specific tips that are useful for me and, finally, make some comments on advanced features.

The only limitation that is worth mentioning is the fact that Zotero does not have a built-in pdf reader, as Mendeley (I do not know about EndNote). So, every time you open a PDF stored on your collection, Zotero launches the reader on your system and you have to make notes, highlightings and annotations in it. I actually prefer this way (I like my PDF reader - Okular), but some people may prefer a built-in reader to stay always inside the same environment.

Most of the info in this post is also on this pdf that I used in a presentation at the 2017 PGR Conference - School of Education, University of Nottingham. Feel free to use and distribute it :)

Before the instructions, some comments on the interface. On the left you have the organizational features: collections (similar to folders) and list of tags (on the bottom). On the middle you have your entries (each entry can have sub-items such as the actual pdf file, notes written on zotero, images, etc). On the right you can see the metadata of the entry selected in the middle column (basic info such as authors, title, journal, etc), notes (you can use this features to attach your comments on the entry for instance), tags and a list of related papers. Note that Zotero can fill the basic info for you, but the other tabs have to the generated by you.

scheenshot of Zotero

Setting it up

  1. Download and install it;
  2. Go to Tools → Add-ons → Extensions, and activate the integration with LibreOffice or Word;
  3. Go to Edit → Preference → Sync, and create an account to be able to use groups and access your references in different devices;
  4. Go to Edit → Preference → PDF Indexing, and install the plugin that enables Zotero to get metadata from PDF files;
  5. Go to Edit → Preference → Cite, and mark Use classic Citation Dialog to have access to more options when adding a citation on LibreOffice or Word. I really think this is better than the "modern view";
  6. Create a basic set of Collections (in the column on the left), such as “For the future”, “Unread”, “Favourite”, "Thesis", etc;
  7. Decide if you are going to save all your pdfs in Zotero or not. The advantage of using Zotero for that is that you can easily find the pdf once you found the entry. The disadvantage is that the way Zotero organize the files is not so intuitive, so it is a bit complicated to find a pdf without Zotero.

Using it

The three ways to add a source are:

  1. Using unique IDs, such as DOI or ISSN (click on the wand button). By far the easiest way and recommended if you plan to collaborate;
  2. Dragging and dropping a PDF into the software (then, use the option Extract metadata from pdf after right-clicking the pdf). It does not work sometimes (it depends on how the pdf was generated);
  3. Copying (control+C) the bibtex metadata (from Google Scholar, for instance) and using the option File → Import from Clipboard. Most websites offers bibtex format, but sometimes it is not complete (specially on Google Scholar).

In terms of organization, I recommend to use lots of tags (easier to combine) and be more selective with the Collections. Finally, check regularly the “Duplicated Items” collection to avoid surprise in the future when writing.

Specific tip

This is a suggestion I read online a long time ago and found very useful during my PhD.

Zotero allows you to create collections and subcollections, which can be flexibly reorganized and renamed according to your wishes. My suggestions is: create a structure of collections that mimics the structure of your thesis. Of course you are going to change your mind during the process, but you can reorganize the collections as well to keep some resemblance.

I found this useful to recollect in the future, when you start to actually write up your thesis, the papers you read in the beginning of your research. So, when you get to your Methods section, let's say, you can check the references on your Methods collections. This way, you do not have to rely on your memory.

Advanced features

Zotero's Advanced Search is extremely powerful, allowing you to create searches combining collections, tags, search on all the fields of an entry with regular word searches. Also, it allows you to save the searches in case you want to use them in the future. This can be very powerful if well utilized.

Also, Zotero organizes the metadata in a readable and intelligible database. That is the part I love about open source! If you need to fiddle with the metadata in a way that is not supported by the software, you can open this file using any database tool and read it! And script it!

Embodied cognition and postmodernism

11 Aug 2017 / Leonardo Barichello

The text below is a section of the book "Where mathematics comes from: how the embodied mind brings mathematics to being" by George Lakoff and Rafael Núñez.

As we have just noted, a significant part of mathematics itself is a product of historical moments, peculiarities of history, culture, and economics. This is simply a fact. In recognizing the facts for what they are, we are not adopting a postmodernist philosophy that says that mathematics is merely a cultural artifact. We have gone to great lengths to argue against such a view.

The theory of embodied mathematics recognizes alternative forms of mathematics (like well-founded and non-well-founded set theories) as equally valid but about different subject matters. Although it recognizes the profound effects of history and culture upon the content of mathematics, it strongly rejects radical cultural relativism on empirical grounds.

In recognizing all the ways that mathematics makes use of cognitive universal and universal aspects of experience, the theory of embodied mathematics explicitly rejects any possible claim that mathematics is arbitrarily shaped by history and culture alone.

Indeed, the embodiment of mathematics accounts for real properties of mathematics that a radical cultural relativism would deny or ignore: conceptual stability stability of inference, precision, consistency, generalizability, discoverability, calculability, and real utility in describing the world.

This distinguishes an embodied view of mathematics from a radical relativist perspective. The broad forms of postmodernism recognize the effects of culture and history. But they do not recognize those effects of embodiment that are not arbitrary. It is the nonarbitrariness arising from embodiment that takes mathematics out of the purview of postmodernism.

Moreover, the embodiment of mind in general has been scientifically established by means of convergent evidence within cognitive science. Here, too, em- bodied mathematics diverges from a radically relativistic view of science as just historically and culturally contingent. We believe that a science based on convergent evidence can make real progress in understanding the world.

I think that just the fact that the authors felt the need to clarify why their ideas do not align to the postmodern view is quite interesting. But also, I enjoyed their explanation.

Why multiple representations?

03 Aug 2017 / Leonardo Barichello

I agree with the following statement by Duval (2006):

From an epistemological point of view there is a basic difference between mathematics and the other domains of scientific knowledge. Mathematical objects,2 in contrast to phenomena of astronomy, physics, chemistry, biology, etc., are never accessible by perception or by instruments (microscopes, telescopes, measurement apparatus). The only way to have access to them and deal with them is using signs and semiotic representations. (pp. 107)

If one accepts that statement, it seems reasonable to conclude that representations are particularly important in the teaching and learning of mathematics. However, it does not imply that multiple representations should be at the core of teaching, as several scientific papers and recent official documents place them.

One of the justifications often presented to support the use multiple representations is the following:

Because no single visual representation perfectly depicts the complexity of mathematical concepts, instructors often use multiple visual representations, where the different representations emphasize complementary conceptual aspects. (Rau and Matthews, 2017, pp. 531)

I fundamentally disagree with this view because I understand that some representations are very powerful and may be able to communicate a wide enough (for educational purposes, for instance) range of conceptual aspects of a given concept. Two examples: Hindu–Arabic numeral system to represent quantities and flat drawings made with pen, paper, ruler and compass for euclidean plane geometry.

A second common argument is the idea that multiple representations promote conceptual understanding. The problem with this argument is that since there is no instrumental definition of conceptual understanding, been able to use multiple representations to present a given concept became the definition of conceptual understanding. So, it is not a matter of multiple representations promoting conceptual understanding, but conceptual understanding being multiple representations.

From my perspective, multiple representation is a matter of curriculum: we, teachers, teach multiple representations because they are included in the curriculum directly, as a topic on its own, or indirectly, as a pre-requisite for another topic. That is my stand point in the paper Implications of Giaquinto’s epistemology of visual thinking for teaching and learning of fractions, where I defend the adoption of a carefully chosen visual representation (instead of multiple representation) especially when it comes to low achieving students.

Curiously, my position finds support in the paper published by Rau and Matthews (2017), where the authors draw some recommendations to promote learning through multiple representations. When discussing the limitations of their recommendations, they state that "some visual representations may be intuitively more accessible than others because they align with the structure of human cognitive architecture" (pp. 540). The authors call these representations privileged and point out that "deploying them as anchor representations might help optimize the web of meaning that emerges from use multiple representations" (pp. 540).

That is my point! For some representations there are reasons to use them that go beyond curriculum. Therefore, these representations should stand out of the pool as tools that can actually support learning and, then, the other representations may come to complement specific aspects (if some) or to cover curricular goals.


Duval, Raymond. ‘A Cognitive Analysis of Problems of Comprehension in a Learning of Mathematics’. Educational Studies in Mathematics 61, no. 1–2 (2006): 103–31. doi:10.1007/s10649-006-0400-z.

Rau, Martina A., and Percival G. Matthews. ‘How to Make `more’ Better? Principles for Effective Use of Multiple Representations to Enhance Students’ Learning about Fractions’. ZDM 49, no. 4 (August 2017): 531–544. doi:10.1007/s11858-017-0846-8.

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