Sex and Intimacy are neither one nor the same.
Sex is the physical act of intercourse. It is an external act often driven by an internal emotion. Since emotions are created by our mental state, a mind of clarity is essential. Sex builds upon a euphoric feeling resulting in an orgasm that lasts only minutes. Although there are claims to the contrary it has yet to be proven that any orgasm lasted longer than 5 minutes.
After sex some feel unfulfilled and continue to seek out fulfillment, while others feel contented until the urge hits them again. Sex is easily defined by its external actions.