Throughout history, advancement has come from reducing the amount of work that needs to be done by humans and letting technology do it for us. Long before computers, humans were letting our technology work for us in order to make ourselves better.
So too with programming. We have the ability in PHP, as in many languages, to make the language syntax itself find bugs for us. It's called "types", and is a far too under-utilized part of the language. Even many seasoned developers don't realize the benefits that come from having strict, explicit types in their code rather than relying on haphazard "duck typing".
This talk will make the case that your best way to improve your productivity as a developer is to make your language itself do your work for you. With PHP 7's improved typing support that is now even easier than ever.