There's no single definitive moment when Albert Einstein "decided" he wanted to be a scientist. His fascination with science developed gradually throughout his childhood and adolescence.

Here's a breakdown of the influences:

* Early Childhood: He was deeply curious and fascinated by the workings of the world around him. His father, Hermann Einstein, encouraged his curiosity, providing him with a compass and other tools to explore.

* Age 12: This is often cited as a turning point. He encountered a geometry textbook, which sparked a fascination with mathematics. It was at this point that he started to see science as a potential career path.

* Age 16: He encountered a physics textbook that challenged the prevalent scientific theories at the time. This sparked his lifelong passion for questioning accepted dogma and searching for deeper understanding.

Einstein's journey to becoming a scientist wasn't a sudden decision but a gradual evolution fueled by his innate curiosity, love for understanding, and exposure to scientific concepts at crucial stages of his life.