'On the Soul'(''peri psyche'', প্ৰায়ে ''De Anima''নামৰ লেটিন নামেৰে জনা যায় ) নামৰ গ্ৰন্থত উল্লেখ থকা মতে এৰিষ্ট'লিয়ান মনোবিজ্ঞানত মূলত: তিনিপ্ৰকাৰৰ মনোজগত ( "psyches") ৰ অস্তিত্ব মানি লোৱা হয়৷ এইবোৰ হৈছে- আংগিক মনোজগত (vegetative soul),সংবেদনশীল মনোজগত ( sensitive soul) আৰু যুক্তিসম্পন্ন মনোজগত (rational soul) ৷ তেওঁৰ ধাৰণা অনুসৰি মানুহৰ মনোজগত হৈছে যুক্তিসম্পন্ন মনোজগত৷ এই মনোজগতৰ বাকী দুবিধৰ দৰেই ক্ষমতাসমূহ আছে৷ উদাহৰণস্বৰূপে ই আংগিক মনোজগতৰ দৰেই বৃদ্ধ পাব পাৰে,পৰিপুষ্টি লাভ কৰিব পাৰে আৰু সংবেদনশীল মনোজগতৰ দৰে ই অনুভৱ কৰিবও পাৰে৷ আনহাতে যুক্তিসম্পন্ন মনোজগতৰ একক ক্ষমতা হ'ল এয়ে যে ই যুক্তিৰে বিভিন্ন ধাৰণাৰ তুলনা কৰিব পাৰে৷ <ref>Stanford Encyclopedia of Philosophy, article [http://plato.stanford.edu/entries/aristotle-psychology/ "Psychology"].</ref>
Aristotle's [[psychology]], given in his treatise [[On the Soul]] (''peri psyche'', often known by its [[Latin]] title ''De Anima''), posits three kinds of [[soul]] ("psyches"): the vegetative soul, the sensitive soul, and the rational soul. Humans have a rational soul. This kind of soul is capable of the same powers as the other kinds: Like the vegetative soul it can grow and nourish itself; like the sensitive soul it can experience sensations and move locally. The unique part of the human, rational soul is its ability to receive forms of other things and compare them.
For Aristotle, the soul (''psyche'') was a simpler concept than it is for us today. By soul he simply meant the [[Hylomorphism#Body-soul hylomorphism|form]] of a living being. Since all beings are composites of form and matter, the form of living beings is that which endows them with what is specific to living beings, e.g. the ability to initiate movement (or in the case of plants, growth and chemical transformations, which Aristotle considers types of movement).<ref>Stanford Encyclopedia of Philosophy, article [http://plato.stanford.edu/entries/aristotle-psychology/ "Psychology"].</ref>
