学说 (xué shuō) is a neutral, academic term for a systematic theory or doctrine (e.g. a scientific or philosophical theory). In contrast, 主义 (zhǔ yì) often carries political or ideological weight and functions like an “-ism” (e.g. 马克思主义); 教条 (jiào tiáo) has a negative connotation, referring to rigid, unquestioned dogma. Use 学说 when focusing on the intellectual content, not its ideological label or dogmatic status.