My enduring memory of Jon was as a first-year PhD student. Having just started at the FIL, I joined the departmental retreat in the hills above Zurich. On our arrival, Jon suggested that a few of us take a walk to the lookout above the hotel. I was unsure whether it was appropriate to join - I had never met Jon before and I felt nervous about being in the presence of someone who's work I had studied as an undergrad! But as we walked he made a point to include me in the conversation, and grilled me about my plans for my first experiment. At the time I was obsessed with the question of whether altering the rewards available for particular perceptual decisions changes perception (phenomenology) or just biases our responses towards the more rewarding option. My idea was to use fMRI to answer this question - if rewards change activity in visual cortex, then we could claim an effect on perception. Jon took the time to point out to me all the potential flaws in this logic and my experimental design, at a speed I found difficult to assimilate. But back at the hotel, feeling slightly deflated and assuming our conversation was over, he made a beeline for me at lunch to say - "just to be clear, I think you should definitely do the experiment. Just make sure you do it correctly!". It was exactly the combination of critique and motivation that I needed.
During my PhD Jon continued to take an interest in my progress, offering to read drafts of papers and asking about the progress of postdoc applications. This was all despite him having no formal supervisory role, and at a time when his heavy workload included the directorship of the ICN. He was truly generous in his advice and support to the younger generation and will be dearly missed.