Wir müssen wissen – wir werden wissen. - Epitaph of David Hilbert

We do what we want, because we can. - GLaDOS

Take your pick of rationales, it's not gonna end well for Mr. Squid.

Interestingly, the experiment in Figure 2 was to demonstrate that action potentials could be generated from isolated neurons in buffer solution just as well as they could from an exposed neuron in situ -- so the squid still dies, but it's not tortured to death.