How do you think? People can experience thoughts, feelings, and sensory inputs very differently. While context and substances are known to promote changes in perception and thinking, the biological basis is very diverse, contrary to what is often assumed. Brain cells come in extraordinary varieties in size, shape, and complexity. Their synaptic connectivity provides the foundation of all our sensory input, motor output, cognitive functions, and thoughts. In short: They shape us. This talk gives an introduction about the extent of variability in neuronal patterns that underlies neurodiversity and critically discusses the idea of neurodivergence, diagnosis criteria in Autism and ADHD from a biological and first person-perspective. We find that biological variability of brains is an evolutionary feature that helps us to adapt to our environment but comes with certain risks and downsides in our modern society.