Caturthāṃśa (D-4)

Caturthāṃśa (चतुर्थांश, also written Chaturthamsha or Turyamsha) — the D-4 chart — is the fourth of the sixteen classical Ṣoḍaśa-vargas described in Brihat Parāśara Horā Śāstra. The Caturthāṃśa reads the sukha (fortune in residence, property, domestic well-being, conveyances, landed assets) register of the native, deepening the reading of the 4th-bhāva of the Rāśi-chart. The name caturthāṃśa is Sanskrit for "fourth part" or "quarter- division," naming the chart's computational structure directly. The D-4 is included in all classical graded-varga schemes from Sapta-varga onward.

Classical grounding

Brihat Parāśara Horā Śāstra's Ṣoḍaśa-varga-adhyāya names the Caturthāṃśa's computational rule and its sukha register signification; Bṛhat Jātaka of Varāhamihira chapter 8 names the same scheme; Phaladeepikā and Saravali extend the treatment with classical commentary on the specific property-register applications. The classical framework treats Caturthāṃśa as a specialised reading of the 4th-bhāva register that supplements the Rāśi-chart's 4th-bhāva reading.

Computational scheme

BPHS's division rule for D-4: each 30° rāśi is divided into four 7°30' parts, with rāśi-ownership assigned as follows — the first caturthāṃśa (0°–7°30') is the same rāśi; the second (7°30'–15°) is the 4th rāśi from the same; the third (15°–22°30') is the 7th rāśi from the same; the fourth (22°30'–30°) is the 10th rāśi from the same. The four caturthāṃśas of any rāśi therefore correspond to the four kendras (angular bhāvas) counted from the rāśi itself. Example: Meṣa's four caturthāṃśas are Meṣa (0°–7°30'), Karka (7°30'–15°), Tulā (15°–22°30'), and Makara (22°30'–30°) — the four movable-rāśi set counting from Meṣa. The D-4 scheme maps every 7°30' to a kendra-position rāśi.

Classical significations

The Caturthāṃśa-chart classically reads sukha — the 4th-bhāva signification cluster: fortune in residence, domestic ease, landed property, conveyances (vāhana), the mother-register (one of the classical readings), schooling and formative environment. Classical reading: the 4th-bhāva of the D-4 chart reads the residence- register specifically; the Lagna of the D-4 reads the native's domestic-register orientation; the 4th-lord of the Rāśi placed strongly in the D-4 classically strengthens the overall sukha- reading. Malefic placement in the D-4's 4th or its aspects modifies the property-register assessment. Chandra as the classical mātṛ-kāraka and general sukha-kāraka is cross-referenced in the D-4 reading.

Classical interpretation register

The classical interpretation register of the Caturthāṃśa is sukha- specific — the chart specialises the 4th-bhāva reading of the Rāśi. Classical commentators note that the D-4 is particularly used for assessing the native's relationship to landed assets, vehicles, and residence-register circumstances — including timing-register questions when cross-referenced with Daśā schemes. The vargottama condition in the D-4 (a graha in the same rāśi in D-1 and D-4) occurs only in the first 7°30' of a rāśi and is classically a significant strength-register. The D-4 figures in classical Vaiśeṣikāṃśa scoring from Sapta-varga onward. The D-4 reading is cross-checked with the Rāśi's 4th-bhāva, the 4th-lord placement, and Chandra's condition for complete sukha-register assessment.

Related Concepts

• Rāśi (D-1) — primary chart
• Sukha-bhāva (4th) — 4th bhāva — sukha register
• Chandra — classical mātṛ-kāraka / sukha-kāraka
• Daśāṃśa (D-10) — paired sukha-karma reading