Need of philosophy

दु:ख त्रयाभिघातात् जिज्ञासा तदपघातके हेतौ ।
दृष्टे साऽपार्था चत् नैकान्तात्यन्ततोऽभावात् ।। – सांख्य करिका
Meaning : Curiosity for elimination of unhappiness arises after one experiences adhibhautik (physical), adhidaivik (physical and spiritual combined) and adhyatmik (purely spiritual)suffering. If this desire is fulfilled with visible remedies then what is the need for remedies from philosophy which are invisible ?
As this does not happen, philosophy is required.