The half-life of a neuron microtubule is about ten minutes; the actin filaments in the dendrites last about forty seconds; the proteins that provide energy to the synapses are replaced every hour; the NMDA receptors in synapses are relatively long-lived at five days. So you are completely replaced in a matter of months, which is comparable to the gradual replacement scenario I describe above. Are you the same person you were a few months ago? Certainly there are some differences. Perhaps you learned a few things. But you assume that your identity persists, that you are not continually
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