On Thursday 6th February 2020, 3 – 5pm the London Spinoza Circle will host Martin Lenz (University of Groningen) who will speak on:
Biased Beliefs: Spinoza on the Interaction of Ideas
Location: Birkbeck, University of London, Dreyfus Room, 26 Russell Square, London WC1B 5DQ
All welcome and no registration is required.
Abstract:
Spinoza famously holds that we standardly believe whatever it is that is perceived or goes through our mind, unless we hold stronger beliefs to the contrary. So if you see a winged horse on your lawn, you will also believe that there is a winged horse on the lawn, unless you have strong beliefs excluding the existence of winged horses. Couched in the terminology of the 17th century, Spinoza holds that we cannot merely contemplate ideas, but that every idea involves at least an affirmation. Spinoza’s principle has been well acknowledged in the literature. However, it is rarely considered how this principle is coupled with what could be called the principle of exclusion: we believe something unless a certain thought is excluded by beliefs we already hold. But if we tend to embrace what coheres with previous beliefs, we don’t just believe anything. Rather we might say that our minds are governed by what could be called a constant confirmation bias, i.e. a tendency to confirm existing beliefs. This raises the question of what governs this bias. Why don’t we believe in winged horses? In other words, what is the foundation of including certain beliefs and excluding others?
The exclusion principle, I submit, cannot be understood so long as we merely look at individual minds. Rather, the exclusion principle should be seen as rooted in the assumption that things (and thus also minds) are of a contrary nature. Accordingly, I shall argue that Spinoza’s holds an interactive account of ideas in that their affirmative force is explained in virtue of contrariety. Only when considering opposing ideas (and minds) can we understand why ideas exclude one another in their contrary striving (conatus).
Analysing contrary interactions requires us to focus on the question of what it means for ideas to have a conatus. What does it mean to say that the ideas themselves strive to persevere, rather than the cognitive agents who have ideas? After assessing some individualist answers in the literature (section 1), I will show that it is not any single conatus but the interaction of ideas, set off by contrariety, that governs the striving and determines which beliefs are held. We shall see that the exclusion principle that founds our biases is not a merely logical notion but rooted in the contrary nature of things (section 2). Understanding interaction in terms of contrariety, however, will give rise to a number of objections, the discussion of which will shed some light on the common understanding of the conatus doctrine (section 3). Finally, I will try to situate the emerging account in with a view to current philosophical approaches and show how the exclusion principle lends itself to an understanding of ideas in terms of confirmation bias (section 4).
Schedule of events 2019-20 at the London Spinoza Circle
At the next meeting of the 
spinoza research network 